John weeks



(No Model.)

J. WEEKS. HYDRAULIC JACK.

Patented Dec. 3, 1895.

j ZZZ 7??? WITNESSES:

NlTED JOHN VEEKS, OF NEXV YORK, N. Y., ASSIGNOR TO JOHN F. DETTMAR,EXECUTOR OF RICHARD DUDGEON, DECEASED.

HYDRAULIC JACK.

SPECIFICATION forming part of Letters Patent No. 550,702, dated December3, 1895. Application filed Au ust 27, 1895. Serial No. 560,688. (Nomodel.)

To all whom it may concern.-

Be it known that I, JOHN l/VEEKS, a citizen of the United States, and aresident of New York city, in the county of New York and State of NewYork, have invented certain new and useful Improvements in Hydraulic Jacks, of which the following is a specification.

My invention relates to a new and useful improvement in hydraulic jacks,whereby the parts are so constructed and arranged that the operation ofthe jack is rendered more certain, absolute, and safe, and whereby it isadapted to use more safely than most forms of jacks now known in thehands of unskilled or even ignorant persons.

Generally stated the invention consists in making the parts in suchmanner that the pump is a pump pure and simple and is not complicated byany connection with or relation to the devices for lowering the jack,and the lowering devices are made separate by themselves and areoperated by separate mechanism, and their construction is such thatpositive sealing of the liquid within the chamber under the rear of thejack is accomplished. ram, the escape of this liquid can be adjustedeven to infinitely-small degrees, so that the lowering may be rapid orexceedingly slow, as desired. This is sometimes of great importance.

The drawing hereof illustrates a vertical longitudinal section of acomplete jack, the pump, plunger, and backfiow valve-stem being shown inelevation.

A is the cylinder of the jack. B is the base. 0 is the ram. D is thehead. E is the knuckle. F is the pistonrod. G is the piston. These partsare or may be the same as usual and are all provided with the usualparts. The details of some of them are not shown, since they are toowell known to require special description.

II is the pump-block. It is provided with screw-threads I, which engagewith corresponding threads in the ram 0, whereby the pump-block isfirmly held to the ram, but may be easily removed therefrom by simplyunscrewing it.

J is an annular shoulder, which rests against the lower end of the ramto aiford firm sup \Vhen it is desired to lower the port for thepump-block against the pressure from below.

K is the usual cup-packing provided with a packing-ring L to seal thejoint between the ram and the cylinder. The packing-ring L threads upona downwardly-projecting portion of the pump-block and a portion of thering extends below the pump-block, and to it is threaded a bonnet M,which is provided with the usual water-passages N N, &c.

O is the egress-valve from the bore of the pump to the chamber below theram, and it is received within a recess in the upper side of the bonnetM, as usual. A small spiral spring P aids in reseating this valve.

Q is a vertical passage bored through the pump-block by the side of thebore of the pump proper, and, if desired, the bore of the pump maybe seteccentric to the actual line of the pump-block, so as to leave moremetal on one side than the other to provide space for this passage Q.

R is another passage made in the upper surface of the bonnet M, whichconnects with the lower end of the passage Q.

S is the stem for the egress-valve, the valve T itself being formed onits lower end, and it is seated at the upper end of the passage Q.

U is a spiral cone-shaped spring, (any other suitable form may be used,)which normally elevates the stem S, unseating the valve T at its end.

V is "a bell-crank lever pivoted at \V to the head of the jack andprovided with a spring a, whereby it is normally tipped upwardly.

b is a screw plug or bolt having a squared end 0, which is receivedwithin a recess d in the head of the jack, and the plug is provided witha packing e.

f is a detachable hand wheel or key having a squared socket adapted tofit over the squared end 0 of the screw-plug (Z. The inside end of thescrew-plugbears against an upwardly-extending finger g of thebell-crank.

The operation of the invention is as follows During the operation ofpumping up the jack the lever (not shown) is manipulated in the ordinaryway; but no 'eare is necessary in so doing, because there is nopossibility of striking the egress-valve 0, its spindle being entirelybelow the lowermost portion of the pump-bore, and a man, irrespective ofhis intelligence, can safely operate the machine, because there is nodanger of his injuring it or of his striking the egress-valve, thuscausing the load to jump or shiver, as it is called. After the load hasbeen lifted to the desired distance and it is desired to lower the jackthen the operator or foreman takes the key from his pocket or othersuitable place and with it runs back the screw-plug (1, whereuponpressure on the finger g of the bellcrank V is removed and the spring aand also the spring U elevate the devices V and S, thus removing thevalve T on the end of the spindle S the desired distance from the upperend of the passage Q, whereupon the liquid from the chamber below theram passes in reverse directiont'. e., upwardly through the passages N NN, thence alternately through the passage R and vertically through thepassage Q, and thence through the valve T back to the head of the jack.Consequently the pressure in the lower chamber being relieved the jackis lowered.

It will be particularly observed that under my invention the sealing ofthe lower chamber is rendered absolute, because the valve '1 is seatedon the upper end of the channel Q, by the positive action of thescrew-plug b, when manipulated by the key or hand-wheel f. Thus this maybe made a securely-.close ;l joint, more so than when the egress-valveis allowed to rest itself, as is now commonly the practice. Also, asbefore stated, no lack of experience 011 the part of the operator caninjure either the pump or the egress-valve or the piston, and also (thisis an important matter) the rapidity with which the liquid is allowed toescape from the lower chamber can be regulated with great exactness,more so than when this operation is performed by manipulation of thepumping-lever.

It will be obvious to those who are familiar with this art thatmodifications may be made in details of construction of the parts shownwithout departing from the essentials of the invention. I therefore donot limit myself to these details.

I claim 1. In a hydraulic jack, the combination of a pump detachablefrom the ram, and which discharges into the chamber below the ram, aback flow passage made in the pump, separate and distinct from the borethereof, a bonnet at the lower end of the pump having a water passageconnected with the said back flow passage, a valve actuated by a bellcrank and a screw plug actuated from the eX terior of the jack, whichoperates said bell crank, for the purposes set forth.

2. In a hydraulic jack, the combination of a pump discharging into thechamber below the ram, a back flow passage made in the pump, separateand distinct from the bore thereof, a valve actuated from the exteriorof the jack and a spring whose normal tend ency is to unseat said valve,for the purposes set forth.

3. In a hydraulic jack, the combination of a pump discharging into thechamber below the ram, a back flow passage made in the pump, separateand distinct from the bore thereof, a valve which closes said back flowpassage, a lever to close it, a spring to open it, and means operatedfrom the exterior of the jack to actuate said lever, for the purposesset forth.

Signed at New York, in the county of New York and State of New York,this 23d day of August, A. D. 1895.

JOHN \VEEKS.

\Vitnesses PHILLIPS ABBOTT, H. H. ST. CLAIR, Jr.

